The number 97 on a tire represents its load index, which indicates the maximum weight capacity a single tire can safely support when properly inflated.
Specifically, a tire with a load index of 97 means it can carry a maximum load of 1,609 pounds (730 kg). This value is crucial for ensuring vehicle safety, performance, and compliance with manufacturer specifications.
Understanding the Tire Load Index
The load index is a numerical code found on the tire's sidewall, usually as part of the tire's service description (e.g., 205/55R16 97V). It's a standardized system that translates to a specific weight capacity. This number is not the actual weight the tire is currently carrying, but rather the maximum weight it can support.
Why the Load Index Matters
- Safety: Using tires with an insufficient load index can lead to tire failure, loss of control, and accidents, especially when the vehicle is fully loaded.
- Performance: Tires with the correct load index contribute to optimal vehicle handling, braking, and overall stability.
- Tire Longevity: Overloading tires, even slightly, can cause excessive heat buildup, premature wear, and structural damage.
- Vehicle Specifications: Vehicle manufacturers specify a minimum load index for the original equipment tires to match the vehicle's Gross Vehicle Weight Rating (GVWR) and Gross Axle Weight Rating (GAWR). It's essential to replace tires with ones that meet or exceed these specifications.
Common Load Index Values and Their Capacities
To give you a broader perspective, here are some examples of load indices and their corresponding maximum load capacities:
| Load Index | Load (lbs) |
|---|---|
| 97 | 1609 |
| 98 | 1653 |
| 99 | 1709 |
| 100 | 1764 |
For a comprehensive list, you can refer to a tire load index chart.
Practical Considerations
When purchasing new tires, always ensure that their load index is equal to or greater than the vehicle manufacturer's recommendation. This information can typically be found:
- On a sticker inside the driver's side door jamb.
- In the vehicle owner's manual.
- Inside the glove compartment door.
Mismatching load indices can compromise vehicle safety and performance, making it a critical factor in tire selection.
